The Geography of the Clear Creek Watershed

Clear Creek Watershed map

The 575-square mile Clear Creek Watershed spans from 14,000-foot mountain peaks at its western edge on the Continental Divide down to the urbanized plains at its confluence with the South Platte River just north of the mile-high city of Denver. 400 square miles of that total are located in the mountains west of Golden. Fully one-third of the watershed lies within the Arapaho & Roosevelt National Forests and is administered by the Clear Creek Ranger District. Such a locale makes Clear Creek a prime model of an arid mountain west watershed in which to pilot and prove tools and techniques for sustainable watershed management.

Clear Creek’s headwaters begin in an area rimmed by four “14-ers”—Grays and Torreys Peaks, Mt. Evans and Mt. Bierstadt. Major tributaries include the North, South and West Forks; Leavenworth, Lion, Trail, Chicago, Soda and Ralston Creeks; Fall River; and Beaver Brook. The mainstem flows eastward along the I-70 corridor through several mountain communities, along approximately 12 miles of the Highway 6 corridor through Clear Creek Canyon, and then back along the I-70 corridor through several Denver Front Range communities. Clear Creek converges with the South Platte River near Commerce City.

Clear Creek and its tributaries serve as the primary water supply source for several upper-watershed towns (Silver Plume, Georgetown, Empire, Idaho Springs, Black Hawk, Central City) and industries, including Loveland Ski Area and Henderson Mine, which are located in Clear Creek County and Gilpin County.

Clear Creek is the principal surface water source for numerous lower-watershed entities as well—Coors Brewing Company, many agricultural users (ditch companies), the City of Golden, Arvada and Standley Lake Reservoir, which provides potable water to more than 350,000 residents in the cities of, Northglenn, Thornton, and Westminster. Lower watershed counties include Jefferson, Adams, and a small portion of Denver.

The demand on Clear Creek makes it one of the most over-appropriated streams in Colorado. In addition to offering numerous recreational opportunities, Clear Creek is also a prime riparian and wildlife habitat. Clear Creek Watershed is included within the South Platte River Watershed, which in turn feeds into the Mississippi River Watershed, which ultimately flows into the Gulf of Mexico.

The Clear Creek Watersehd is also a location for conflicting national purposes. Since many of the ecologic, sociologic and economic values are concentrated in the watershed valleys, there are unique problems in making it all fit and function. The valleys contain:   

  • National Defense and Homeland Security avenues
  • a transportation interstate highway
  • two National Historic Landmark Districts—Georgetown and Idaho Springs
  • a Preserve America Community named by First Lady Laura Bush—Georgetown
  • a county designated as one of Colorado’s most endangered places—Clear Creek County
  • endangered and threatened fish and wildlife species
  • a conveyance mechanism of clean water
  • a Superfund site

There are parallel agencies and concerns protecting the interests of the State of Colorado. In addition, and perhaps most importantly, there are the interests of the people who live in these valleys and own surface, subsurface and water rights. There is a concentration of varied interests within our watershed that requires an enhanced effort toward cooperative efforts.